Booting From Non-Linear Memory

Abstract

A method and system for booting a microprocessor controlled device. A microprocessor that is designed to read from a linear storage device executes code from a non linear storage device through an interface or emulator that writes and retrieves specially formatted boot instructions to / from the non linear storage device.

Description

CROSS REFERENCE [0001] This application is a continuation application Ser. No. 10 / 263,576, filed on Oct. 2, 2002, which application is incorporated herein in its entirety by this reference. [0002] The attached source code on CD ROM also forms part of this description and is hereby incorporated by this reference in its entirety in accordance with 37 CFR 1.52 as an appendix containing the following files: 02085—0938\CPU_NAND_If\.cmd_decode.vhf, 1 / 31 / 02, 2 KB; 02085—0938\CPU_NAND_If\int_out_bus_mux.vhf, 1 / 31 / 02, 2 KB; 02085—0938\CPU_NAND_If\io_buff_control.vhf, 1 / 31 / 02, 2 KB; 02085—0938\CPU_NAND_If\nand—8_bit_if.ucf, 9 / 18 / 01, 2 KB; 02085—0938\CPU_NAND_If\nand_ce.vhf, 1 / 31 / 02, 2 KB; 02085—0938\CPU_NAND_If\nand_control-signals.vhf, 1 / 31 / 02, 7 KB; 02085—0938\CPU_NAND_If\nand_cpu_bus.vhf, 1 / 31 / 02, 6 KB; 02085—0938\CPU_NAND_If\nand_rd_control.vhf, 1 / 31 / 02, 3 KB; 02085—0938\CPU_NAND_If\nand_reset_control.vhf, 1 / 31 / 02, 5 KB; 02085—0938\CPU_NAND_If\nand_wp.vhf, 1 / 31 / 02, 2 KB; 02085—0938\CPU_NA...

AI Technical Summary

Benefits of technology

Significantly reduces startup time for microprocessor-controlled devices, such as cellular phones and computers, by allowing direct execution of boot code from non-linear storage, reducing costs and improving compatibility with various processors.

Problems solved by technology

Furthermore, there is no standard dictating a logical order in which the areas are read or executed from.

However, some types of storage devices such as flash memory, specifically NAND and AND type flash memory, are not linearly addressable.

This means that the processor cannot read or execute code from them upon bootup.

However, unlike in linear storage devices, if a page is, for example, 528 bytes in length, byte number 255 cannot be read without first reading the preceding 254 bytes.

Furthermore, reading just one byte is a relatively more complicated procedure that does not follow the typical timing requirements of linear memory.

This has, until now, made booting from non linear memory an impossible task.

Waiting for a device to boot-up is extremely frustrating, whether it be a cellular phone, a computer, portable organizer, or any other smart device.

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